in this morning's "healthwatch dwherkts mammogram debate. breast cancer is the second deadliest form of the disease among women. last year it killed 40,000 americans, but there is still no agreement on how and when and how often to screen for it. on wednesday, the american college of obstetricians and gynecologists say annual mammograms should be offered to all women starting at 40. two years ago, a government panel recommended waiting until age 50. so we're looking for clarity on this life and death issue. we get it from cbs news medical correspondent dr. jennifer ashton and nancy brinker, founder and ceo of the susan g. komen foundation. great to have you both with us. obviously, a really important topic to so many people. and we have heard, jen, glins changing and evolving. how have they changed and evolved over time? >> really, we were in front of this story, rebecca, when it came out in 2009 and cbs extensively covered it.